The long-term objective of this proposal is to develop through a cooperative agreement a clinical network, the Adolescent Medicine HIV/AIDS Research Network, to plan and develop research on the medical, biobehavioral, and psychosocial aspects of HIV/AIDS including access to care and its utilization in adolescents age 15-19 years who became HIV- infected through sexual or drug-taking behaviors. A second objective is to develop and disseminate treatment and policy guidelines specific to HIV- infected adolescents. The cooperative agreement will involve participation in a program of research and evaluation with representatives from a Clinical Science Group, Basic Science Group, and Data and Operations Center as well as National Institute of Health and Health Resources/Services Administration scientific and program staff. The goal of the research to be developed is to understand the natural history of HIV infection in adolescents as well as factors of co-morbidity with the ultimate goal of developing guidelines for clinical management of adolescents with HIV infection and disseminating these guidelines of health care. The initial process will be to enroll approximately 200 HIV-infected adolescents into a base protocol that will evaluate issues related to spectrum of disease, disease progression, and the effect of co-morbidity with sexually transmitted disease and pregnancy. A secondary goal will be to develop and answer questions through special studies concerning HIV infection in adolescents. Dr. Linda Levin, the Principal Investigator, will represent the consortium of Mount Sinai Medical Center and St. Lukes/Roosevelt Medical Center on the Clinical Science Group in the Research Network. During Phase 1 of the project the Clinical and Basic Science Groups will be active in establishing the research agenda, developing the base protocol and clinical management guidelines. In phase II of the first year of the project, the consortium will be responsible for recruiting and enrolling 20 HIV-infected and 10 HIV-negative adolescents age 15-19 years in the base protocol.